VOA慢速英语:Commodity Prices Reach a Two-Year High

1.He says demand in developing economies can push up prices for commodities like oil and iron ore used for making steel.

push up推上去; 增高, 提高

例句：If you can't ride your bike to the top of the hill, you'll have to push it up.
      如果你没有办法把车骑到山顶, 那么你得把车推上去。

      What's pushing up the price of oil?
      什么促使油价上涨?

2.Futures contracts are agreements between a buyer and a seller to exchange something at a set price at some time in the future.

sometime、some time、sometimes、some times这些词或词组在初中我们就都接触过了，但是未必所有的英语学习者都能够清楚地进行区分和准确无误地运用。许多人对它们的理解都还很模糊。现在，我们来逐个击破。
　　sometime
　　(1)副词：某个时候。可指过去或将来的某个时候。如：
　　① Would you come to the cinema with me, sometime? 赏脸找个时间和我看场电影吗？(将来)
　　② We’ll take our holiday sometime in August. 我们会在八月找个时间度假。(将来)
　　③ I bought this sometime last summer. 这是我在上个夏天买的。(过去)
　　④ This mansion was built sometime around 1980. 这栋大厦是1980年左右建的。(过去)

　　(2)形容词：前，过去的。意思类似former。
　　① This is our sometime general manager.这是我们的前任总经理。
　　② Our sometime classmate, Rose, is now a pop star. 我们以前的同学罗斯，现在是明星了。

　　sometimes 副词：有时候。顺便提一下，at times也是“有时”的意思。
　　① Every man is a fool sometimes, and none at all times. 每个人有时都会犯傻，但没有谁会一直都傻。
　　② I sometimes have letters from him. 有时我会收到他的来信。

　　some time 某段时间。常与for连用。
　　① We plan to stay in Hainan for some time. 我们打算在海南呆上一段时间。
　　② I will keep the computer for some time, so you can use it.这部电脑我会留着一段时间，你可以用。

　　some times 几次。several times也可以表示“几次”，但比some times较确定。time作可数名词时可作“次数”解；表示“时间”时是不可数名词。
　　① I am sure that we have met some times before.我肯定我们之前见过几次了。
　　② The newly bought microwave oven failed to work some times.新买的微波炉坏了几次了。

3.He says only this will let them gain from world trade.

only，只有这样才能……

为了强调only及其所修饰的状语（通常是副词、介词短语或从句），则将它们移到句首，句中的主谓作部分倒装。如：

Only then did we realize that the man was blind.

直到那时我们才发现那个人是盲人。

Only when the war was over in 1918 was he able to get happily back to work.

直到1918年战争结束后，他才得以愉快地重返工作岗位。